New Hampshire: no OBD emissions inspection

New Hampshire doesn't test cars by their OBD readiness monitors, so a monitor that isn't ready won't stop a registration there.

Not confirmed: New Hampshire doesn't publish a current rule in its own rules that we could find. Check with the state before you go.

Official source: New Hampshire (checked October 6, 2026). States change their rules; check there before you go.

Every state's rules